Dobby for looms



sept. 4, 192s.'-

1,682,791 J. T. MALLOY DoBY #on Looms Filed April 29, 1927 2 sheets-sheet 1 ZZ ,l 1

Sept. 4, 1928.

J. T. MALLOY DOBBY FOR LOOMS Filed April 29, 192? 2 sheets-sheet 2 atentcd Sept.. 4, 1928.

UNITED STATES,

PATENT OFFICE.

JMES T. MALLOY, F AIKLAND, RHUDE ISLAND, SSGNOR T0 DRAl-"ER CORPORA- TION, 0F HOPEDALE, MASSACHUSETTS, A. CORPORATIQN 0F MAINE Donar non Locus.

Application med April 29, 1927. Serial No. 187.8454.

The present invention relates to an improvement in dobbies for looms.

lt is now the ordinary practice in dobby looms to provide reciprocating knives which cooperate with hooks connectedwith the harness jacks to form the shed. The hooks themselves are under the control of dobby lingers which are now ordinarily gravity aotuated to lift the hooks from engagement l0 with the reciprocating knives. In recent years the demand lias'become more and more emphatic for looms of higher speed, and while the loom itself might be speeded up, the gravity actuation of the dobby fingers -remalns the same, that is, the lack of posil tive actuation of the dobby fingers has 4limited the speed at which a dobby loom would be run.V

it is the function of the dobby fingers tocontrol the dobby hooks and determine when they shall or shall not engage their respective lmives. When a dobby knife moves inward after having formed the shed and a different shed formation is desired, it is necessary to detach the previously engaged hook from its knife7 and the gravity actuation'of the hooksl has frequent-1y caused uncertainty in the disengagement of the hooks from the knives. This has been emphasized in the form ot' dobbies heretofore employed by the fact that the lifter fingers would place the dobby hook under stress and either cause the dobby hook to be cammed off its associate ife or suddenly sprung from engagement therewith at the end of the knifesV stroke, with the result that imperfect cloth has frequently been produced.

rlhe object of the invention is to improve the construction of dobbies in order to render them more certain in operation and durable in construction. To these ends the invention consists in the dobby mechanism hereinafter described and particularly defined in the claims.

in important feature of the present in-l the preferred form of the invention, Fig. 1 is an elevation of the dobby ngers, dobby hooks, dobby levers and harness jacks, showing the pattern chain in position with relation to the dobby lingers; Figs. 2, 3, 4 and 5 areother similar views omitting the jacks showlng the parts in different positions which they assume in operation.

The illustrated embodiment of the invention is described as follows The harness jacks 7 are pivotally mounted at 8 on the dobby frame. The dobby levers 9 are pivoted at 10 to the jacks 7 and normally rest. against the lever stops 11 and 12 of the dobby frame. These dobby levers extendupward and downward from their pivots and at their ends have pivoted to them the top dobby hooks 13 and bottom dobby hooks la. The jacks are normally held in their left hand positions by the weight of the harnesses and by the pull of the harness springs. A top actuating knife 15 and a bottom actuating knife 16 are employed in the usual manner to actuate the harnesses through the hooks, levers. jacks and usual connections. The knives 15 and 16 are reciprocated .in the usual manner for these purposes. The top set of dobby hooks 13 is provided with a top hook rest 17, the bottom set of dobby hooks 14 is provided with the bottom hook rests 18. When the hooks are supported by their rests they occupy their lower positions and their hooks are in position to be engaged by the dobby knives 15 and 16. The selection of the particular harness to be actuated isby means of the dobby ngers 19 pivoted at their ends on the linger shaft- 20. The dobby fingers are adapted to be supported by a linger support 21 when not raised to elevated position. Each dobby finger supports a push rod 22, the upper end of which is adapted to engage a top dobby hook 13. Each dobby nger is also provided with a bottom'dobby hook engaging portion 23 for engaging one of the bottom dobby hoolrs to lift it so that the knife may pass under it without engagement therewith. vrlhe dobby fingers normally rest upon the Enger -support 21 and. are raised hy a pattern chain which carries a series of risers and sinlrers for engagement with the lingers to raise or lower them. aThis 'pattern chain is indicated ina generali wey by the reilerence character 2t and in the plane of one dobby Enger it carries a series of risers and sinlrers arranged iid in such order as to actuate one of the dobby fingers in a prescribed manner to secure the desired weave pattern. Thus for the dobby finger as shown in Fig. 1, the pattern chain is provided with a. riser 1, a sinker 2, ariser 3, a. riser 4, a sinker 5, and so forth, the complete seriesi being a sinker and two risers whereupon the pattern is repeated. The dobby chain is of the well-known form consisting of bars extending from side chain to side chain, upon which bars are carried tubular sinkers and risers or rolls, the sinkers I spacing the risers and holding them in fixed position on the rods. The pattern chain passes over a barrel 25 under the series of dobby fingers and the risers are supported by the barrel inposition to lift the fingers in proper order and to the desired distance. The risers, one after the other, come in Contact with the chain engaging swell 26 of the dobby fingers 19.

This dobby is of the single index type, each finger actuating both a top and a bottom hook. The pattern chain moves in the direction of the arrow 27 and it moves the dobby finger to raise it and to permit itto fall as determined by the risers and sinkers of the chain. When the pattern chain moves a riser out from under the dobby finger and a sinker is next presented, as in moving the riser 1 out from under the swell 26, it causes the finger to fall by reason of the 'presentation thereto of a sinker as a result of which both hooks controlled by this finger are lowered.- One of these hooks will be in position to be er1- gaged by its actuating knife but the other will not be in position to be engaged by its actuating knife because the knife only comes into engagement with a hook in its inward position. iVhen the pattern chain moves the sinker 2 out from under the finger` the rises 3 engages the finger and lifts it. The movetreme inward position and by this timethe pattern chain will have advanced so that the riser 3 will have liftedthe dobby finger 19 and through the push rod 22 it will havelifted its top dobby hook 13 see Fig. 1 and will hold it lifted until the top knife 15 has moved outward beyond the top hook controlled by this dobby finger. The -bottom hook engaging portion 23 of the dobby finger 19 does not engage the bottom dobby hook at this time because of the curve or bend in the dobby hook at 28. Each bottom dobby hook 14 is of the form shown in the drawings. From its pivot 29 at the lower end of the lever 9 it rises upward and extends to the right above the extreme uppermost position of the dobby hook engaging portion 23 of the dobby finger 19. Thus the bottom dobby hook is pre vented from being engaged by the dobby finger while the lower knife is engaged by such dobby hook. (See Fig. 1.) The dobby hook from the bend 28 extends out-ward and downward to the point 30 where it bends again slightly upward and extends in this direction to its extremity where the hook is located. vWhen the bottom knife 16 is moving inwardly the hook engaging portion of the dobby finger is lowered slightly as shown in Fig. 2, so as to'prevent it from camming the hook off the knife. Thus when the riser 3 passes out from under the dobby finger the latter is lowered slightly before the next riser 4 when the pattern chain engages the dobby finger. (See Fig. 2.) lIn the position of the parts shown in this figure. the bottom knife 16 is moving inwardly, the top knife 15 is moving outwardly. In Fig. 3. the riser 4 is shown as having reached the dobby finger and in position about to engage it for the lpurpose of lifting the lower dobby hook 14.

l/Vhen the bottom knife 16 reaches its extreme inward position as .shown in Fig. 4, the riser 4 has started to engage and lift the dobby finger 19 so as to prevent the knife 16 from engaging the hook 14 upon the next outward movement of the bottom knife. This riser 4 not only lifts the bottom hook 14 but through the push rod 22 it also lifts the top lhook 13, but at this time the top knife 15 is out and consequently the lift of the top hook is ineffective to produce any action or inaction of. the parts. After the riser 4 passes out from under the swellI on the bottom of the dobby finger 19, that is, when the riser 4 passes from the position shown in Fig. 5 beyond its active position, then the sinker 5is brought under the dobby finger and the latter remains in its lowered position with both hooks 18 and 14 down. This position will be maintained until after the top knife 15 has made-its movement to the left to the position shown in Fig. 1, whereupon the sinker being under the dobby finger, the top hook will be engaged by the top knife and actuated to lift the harness through the means described. I n the pattern arrangement shown in the next inward movement of ythe lower knife 16, the hook 14 will be caught by the knife and the cycle of operations described will be repeated. It is to be observed that the pattern chain advances a. distance on each reciprocation of a knife corresponding to the spacing between successive bars carrying the risers and sinkers. On Fig. 1 is a diagram which lindicates the timing of parts. Thus, inv Fig. 1 the diagram shows the time of one complete revolution of the loom l@rank as the are of movement of 180 lll on the diagram. The point 3l is the position occupied by the loom crank when the knife 16 is at the position shown, that is. when 1t is out. In Fig. Q the crank will have advanced to the position shown at 32 in that ligure. In Fig. 3 the crank is shown as having advanced still farther, and as havingr arrived at the position 33 at which the knife is about to disengage from the hook. In Fig. 4 the point 3l represents the position of the knife at the end of one complete revolution ot the loom crank. In Fig. 5 the point- 35 is shown at. the position which it occupies when the knife has moved outward to a position in which it is about to pass the hook. Thus` Figs. l, Q 3 and 4 show the movement of the parts through one revolution of the loom crank, and Fig. 5 shows the first position thereafter assumed by the parts.

Having thus described the invention, what is claimed is zl. .A single index dobby for looms having, in combination, harness jacks, dobby levers connected thereto, top and bottom dobby hooks attached to the dobby levers, top and bottom hook actuating knives, dobby fingers pivoted at one end and directly engaging the bottom dobby hooks to positively raise them, push rods connecting the lingers with the top dobby hooks to positively raise them and a pattern chain having risers and sinkers, said bottom hooks and fingers being so shaped that a top hook may be raised by the lifting of a linger without engagement of the latter with a bottom hook to prevent cumming the bottom hook from its knife as the latter moves from its outer to its inner position.

2. A single index dobby for looms having, in combination, harness jacks, dobby levers connected thereto, top and bottom hooks attached to the dobby levers, top and bottom hook actuating knives, dobby fingers pivotally mounted at their outer ends and directly engageable by their non-pivotal ends with the bottom dobby hooks to positively raise them, push rods actuated by the non-pivotal ends of the fingers to positively lift the top dobby hooks, a pattern chain having risers and sinkers for acting directly on the dobby lingers between the pivot mounting and the dobby hook lifting ends, and concaved lower faces formed on the dobby hooks adjacent their pivotal connection with the dobby levers to clear the dobby hooks from engagement by the lifting ends of the lingerswhen the latter are under control of a pattern riser.

3. A single index dobby for looms having, in combination, a harness jack, a dobby lever connected thereto, top and bottom hook actuating knives, a dobby finger pivoted at its outer end, a bottom hook attached to the dobby lever and directly engageable by the free end of the dobby finger to positively raise the bottom hook, a top hook attached to the dobby lever, a push rod mounted on the non-pivotal end of the dobby linger and directly engageable with the top dobby hopk to positively raise it, concaved lower faces formed on the dobby hooks, and a pattern chain havingriser rolls for positively lifting the dobby finger and then permitting the dobby linger to be slightly lowered while still engaged by the riser that. the hooks may not be cammed upward by the dobby finger as the dobby hook moves inwardly in connection with its hook actuating knife.

4i. A single index dobby for looms having, in combination, harness jacks, dobby levers connected thereto, top and bottom hooks attachedto the dobby levers, top and bottom hook actuating knives, dobby fingers pivotally mounted at their outer ends and extending inwardly to a position between the ends ofthe dobby hooks and directly engageable by their lion-pivotal ends with the bottom dobby hooks to positively raise them, push rods actuated by the non-pivotal ends of the dobby fingers to positively lift the top dobby hooks, a pattern acting on the dobby fingers to etlect positive lifting movements of the dobby hooks, and concaved lower faces formed on the dobby hooks adjacent their pivotal connection with the dobby levers to clear the dobby hooks from engagement by the lifting ends of the dobby fingers and push rods when the latter are in raised position by the pattern chain as the dobby hooks move inwardly.

In testimony whereof I have signed my name to this specification.

JAMES T. MALLOY. 

